NAME
CAD::Drawing::IO::DWGI - Perl bindings to the OpenDWG toolkit
WARNING
This module is intended to serve as a backend to CAD::Drawing and is not
guaranteed to remain interface stable. Do not use this module directly
unless you have a need for higher-speed access than that which is
provided by CAD::Drawing (which also provides loads of other features.)
Just
use CAD::Drawing
AUTHOR
Eric L. Wilhelm
ewilhelm AT sbcglobal DOT net
http://pages.sbcglobal.net/mycroft
COPYRIGHT
This module is copyright 2003 by Eric L. Wilhelm and A. Zahner Co.
This is module is free software as described under the terms below.
Permission to use, modify and distribute this module shall be governed
by these terms (the module code is distributed and licensed
independently from the OpenDWG consortium's code.) All notices and
disclaimers must remain intact with any copies of this software.
LICENSE
This module is distributed under the same terms as Perl. See the Perl
source package for details.
REQUIREMENTS
You must obtain and install the OpenDWG libraries from the OpenDWG
consortium in order to use this module. By using this module, you have
the responsibility to adhere to both the licensing of this module and
the licensing of the OpenDWG consortium.
SYNOPSIS
use CAD::Drawing::IO::DWGI;
$dwg = CAD::Drawing::IO::DWGI->new();
$dwg->loadfile("file.dwg");
$dwg->getentinit();
while(my($layer, $color, $type) = $dwg->getent()) {
my $type = $dwg->entype($type);
if($type eq "lines") {
$line = $dwg->getLine();
}
}
$dxf = CAD::Drawing::IO::DWGI->new();
$dxf->newfile(1);
$dxf->getentinit();
$dxf->writeCircle({"pt"=>[$x, $y], "rad" => 1.125, "color" => 9});
$dxf->savefile("check.dxf", 1);
SPEED
Wow! This is fast! I had originally implemented this with a
function-call based wrapper which had the drawback that the layerhandle
had to be found for every object which was being saved. See the
writeLayer() and setLayer() functions below for details of the improved
methods. Also note that while the speed is amazing from this level, very
little speed is lost by moving up a level to using CAD::Drawing (please
do this.)
Accuracy
The dxf file accuracy is set internally at 14 digits after the decimal
place. Providing an interface to set this would take a bit of coding in
C, so you are more than welcome to submit a patch.
Changes
0.08 First public release
0.09 Fixed error reading image size
0.10 Added Ellipse read
Constructor
new
Creates a new blessed reference which gives access to the following
object methods.
$d = CAD::Drawing::IO::DWGI->new();
File Actions
loadfile
Loads a file from disk into the toolkit data structure.
$d->loadfile("filename.dxf|dwg");
newfile
Creates an empty data structure and initializes some default values.
$d->newfile($version);
savefile
Writes the data to disk.
$d->savefile($name, $type);
Layer Actions
listlayers
Returns a list of layers in the loaded object.
@layers = $d->listlayers();
writeLayer
Add a new layer to the database and set it as the current layer. A
newfile() starts with layer "0" as the default.
%layer_opt = (
name => $name, # limit of 255 characters?
color => 9, # must be 0-256
);
$dwg->writeLayer(\%layer_opt)
Currently, the only parameter supported is the name and color.
setLayer
Set layer as the default. Layer must have been previously created with
writeLayer().
$dwg->setLayer($name) or die "layer not in drawing yet";
Typed Entity Functions
NOTE that all getThing methods must be part of a getent() loop.
getCircle
Reads a circle from the current entity.
$circle = $d->getCircle();
print "point: ", join(",", @{$circle->{pt}}), "\n";
print "rad: $circle->{rad}\n";
writeCircle
Writes a circle to the object structure.
$d->writeCircle({"pt"=>[$x,$y,$z], "rad"=>$rad, "color"=>$color});
getEllipse
Reads an ellipse from the current entity.
$el = $d->getEllipse();
print "center: ", join(",", @{$el->{pt}}), "\n";
print "offset: ", join(",", @{$el->{off}}), "\n";
print "minor / major ratio: $el->{ratio}\n";
print "start / end: ", join(",", @{$el->{angs}}), "\n";
There is (as usual) some discrepency between the odwg docs and the adesk
dxf ref as to wtf this parameter thing is. There are some undocumented
functions in the toolkit, which seem to only reduce the arc-angles. NOTE
that the angles given are relative to the baseline described by the
vector stored in $el->{off}.
getArc
Reads an arc from the current entity.
$arc = $d->getArc();
print "point: ", join(",", @{$arc->{pt}}), "\n";
print "rad: $arc->{rad}\n";
print "radian angles: ", join(",", @{$arc->{angs}}), "\n";
writeArc
Writes an arc to the object structure.
%ArcOpts = (
"pt" => [$x,$y,$z],
"rad" => $rad,
"angs" => [$start, $end],
"color" => $color,
);
$d->writeArc(\%ArcOpts);
getLine
Reads a line from the current entity.
$line = $d->getLine();
print "endpoints: ",
join("\n",
map({join(",", @{$_})}
@{$line->{pts}}
)
), "\n";
writeLine
Writes a line to the object structure.
%LineOpts = (
"pts" => [ [$x1,$y1,$z1], [$x2,$y2,$z2] ],
"color" => $color,
);
$d->writeLine(\%LineOpts);
getText
$text = $d->getText();
print "point: ", join(",", @{$text->{pt}}), "\n";
print "string: ", $text->{string}, "\n";
print "height: ", $text->{height}, "\n";
writeText
%TextOpts = (
"pt" => [$x, $y, $z],
"string" => $string,
"height" => $height,
"color" => $color,
);
$d->writeText(\%TextOpts);
getSolid
getPoint
$point = $d->getPoint();
print "point: ", join(",", @{$point->{pt}}), "\n";
writePoint
%PointOpts = (
"pt" => [$x, $y, $z],
"color" => $color,
);
$d->writePoint(\%PointOpts);
getLWPline
$pline = $d->getLWPline();
print "points:\n\t",
join("\n\t",
map({join(",", @{$_})}
@{$pline->{pts}}
)
), "\n";
print $pline->{closed} ? "closed" : "open" , "\n";
writeLWPline
@pts = (
[0,1],
[5,-2.25],
[7,9],
[4,6],
[-2,7.375],
);
%PlineOpts = (
"pts" => \@pts,
"closed" => 1,
"color" => 255,
);
$d->writeLWPline(\%PlineOpts);
getImage
Reads an image from the current entity.
Entity List handling
Entities are read and written from a list, which must be initialized on
both read and write operations.
getentinit
Initializes the entity list. Call this before adding anything to a
newfile() or before calling getent() after loadfile()
getent
Returns the next entity. This is paired with getentinit() and the two
act as a pair much like the Perl open() and $line = setup.
Utilities
get_extrusion
Returns the extrusion vector of the current entity as an array
reference. Returns undef if extrusion is not set.
if(my $extrusion = $dwg->get_extrusion()) {
print "extrusion is @$extrusion\n";
}
set_extrusion
Sets the extrusion direction of the current entity. Not intended to be
used from Perl (each write function calls this itself if the
value of $opts{extrusion} is set.)
entype
Return a text string for the entity type code.
$type = $d->entype($type);
if($type eq "plines") {
$pline = $d->getLWPline();
}
DESTROY
This function is called under the hood by perl when variables created by
new() go out of scope. You should never call this from your code, but
you can undef() your object and it will get called.
Note that you may in fact need to undef($dwg) to kill your object before
trying to use another one. The toolkit doesn't like to be opened and
closed while objects are in-use, and each object has no way of knowing
whether or not there are other objects in-use. Since I don't feel like
leaking memory with a BEGIN and END setup, you'll just have to live with
this (or make a suggestion for a better setup.)